We're making a product which requires a web service to hook up to an existing database used by one of our other products. Owing to time constraints we need to get this thing up and running pretty quickly. Our web server is Apache on a Linux machine, and the client software for the new product is constrained to communication on Port 80. Our dilemma is that we can't just get a new server in time (Apache can't share port 80) and so the plan is to route requests through the existing Apache server.
I know we can hook Apache up to Tomcat using mod_jk, but what I want to do is overlay Apache Axis on Tomcat to make use of SOAP. I'm currently downloading everything I need to test this out, but not having used Axis before, I'm just curious as to whether anybody has actually tried this before and if so, does it / can it work? If there are going to be any roadblocks stopping me from doing this then a heads-up would be much appreciated.
I can't seem to find anything which says this particular setup will or won't work, apart from a posting on the Ubuntu forums which looks similar to what I'm attempting to do but on closer inspection appears to be different.
So to summarise, what I'm curious about is whether accessing a SOAP Web Service through Apache web server, connected to an Axis / Tomcat combo would work?
I'm assuming for now that with a little jiggery-pokery it should be ok, but I'll admit I'm in unfamiliar territory here so any advice / information would be a big help.
Thanks,
Tom
Having just installed and configured all of the necessary components, it appears that this does work. I'm yet to test whether it allows a web service to work from a client machine properly yet, but all signs look good so far!
I worked on a product that had exactly this setup about a year ago. I'm afraid the details are a bit fuzzy, but I don't remember having any problems with the software stack. If you find you need help, comment back here and I'll try to dig up some more info.
Related
I have a problem with a web service that is installed and started with a .msi that is created with the WiX toolset.
The service can be installed and started on all the machines I tested so far (shown as running in the Services Manager) but on some machines it is not reachable (for example via a browser) and not shown in the list of listening ports on that machine (displayed with 'netstat -a').
I am trying to figure out what's going wrong but I am not really familiar with web service development and configuration. It's a third party service, thus I don't know how it works internally.
A good starting point for me would be to find out, what exactly happens when a service is installed and started during the execution of the .msi-file.
Maybe I could try to tackle the problem on a lower level then.
Below is my code in the ServiceInstall-Element:
<ServiceInstall
Id="ServiceID"
Type="ownProcess"
Vital="yes"
Name="ServiceName"
DisplayName="ServiceDisplayName"
Description="Lorem Ipsum"
Start="auto"
Account="LocalSystem"
ErrorControl="normal"
Interactive="no"
Arguments="action=run">
</ServiceInstall>
The argument is important - without it, the service won't start or run.
Maybe someone else encounterd the same or a similar problem and can help me out.
Thanks already in advance - each hint is appreciated.
EDIT I (15.04.18):
As it might be a problem with the specific service, I will add some further information here:
It's a third party software called CryptoLicensing:
http://www.ssware.com/cryptolicensing/cryptolicensing_net.htm
Part of this software is that specific program, that serves as a License Server and does the license registration, for example in a customer's network.
The service can be run as a Windows application or installed and run as a Windows service. In both cases it should be listening on a (pre-)specified port on the installed machine.
Whenever I start the .exe as an application, everything works as intended. The service is reachable (for example with the browser) and can be accessed from other machines in the network.
When the .exe is installed and started as a service, it does not work as intended on every machine. For example if I install and start the service on my laptop, it is shown as running in the Services Manager, but is not reachable on its assigned URL (not even on the localhost) nor is the specific port displayed in the active listening ports, for example with 'netstat -a'.
The service itself starts without any error messages and does not log any errors or exceptions as it seems to be running without any problems.
I contacted the vendor, but sometimes he doesn't reply quickly and he is not very specific in his replies.
Before asking the question I assumed that it was a problem with the Windows user rights and the WiX installer but during the discussion here I had the feeling that it might a problem with the service itself.
I hope this 'new' piece of information helps in isolating and location the problem.
Thanks to everyone who helped so far!
Hopefully not stating the obvious here, but WiX doesn't do much except populate the ServiceInstall table in the MSI file, so this is about why Windows Installer won't start the service. ServiceInstall table:
https://msdn.microsoft.com/en-us/library/windows/desktop/aa371637(v=vs.85).aspx
Also, this isn't really about ServiceInstall - it's probably about the ServiceControl element in your WiX source, but it's not clear whether that's how you're starting it or if you're starting it manually later on. That does make a difference. What is the error message and where are you getting it, and is it a 1920 or 1921 error (in the context of ServiceControl).
The main reason a service will start on one system but not another is missing dependencies. If your service is C++ based (the post doesn't say) then there are probably dependencies on C runtimes, UCRT runtimes, MFC or ATL runtimes and so on.
First: are you sure this service is intended to run as LocalSystem? (MSDN, SO).
Second: did you check the event logs in detail for anything obvious? If the service is good you should find a hint at least. Something to start with. I find that I sometimes miss the actual logs in the event viewer because it is so "crowded". My take on it: empty the log and stop and restart the service.
Something locking / blocking: If the service installs and runs OK I would suspect other factors such as firewalls (hardware & software), security software in general (anti-virus, malware scanners), network configuration issues (proxies, WINS, DNS and all the complexities involved in networking). Is the service trying to reach an UNC path?
Diverse Machines: What are the target machines? Are they virtual, are they physical, are they test machines, are they operative SOE machines in corporate networks? Are they the same OS version and edition?
Further Ideas: It is not quite related, but maybe skim this list of suggestions for debugging from another answer (I am not sure why it was down-voted, I think it is an OK list to inspire debugging ideas): Windows Application Startup Error Exception code: 0xe0434352 (maybe just skim the bolded words for ideas - Recommended).
sc.exe: And finally, perhaps check the sc.exe tool (Service Control) and see if it can provide you with some useful information for debugging.
sc.exe in the context of killing hung services (sample use).
sc.exe from MSDN
Some further links:
Windows Services Frequently Asked Questions (FAQ). Content seems to be up to date - at face value at least. These guys claim to be experts on services. I have no idea who they are.
Essential Tools for Windows Services: SC.EXE
Run Service Control (sc.exe) command on secure port
After almost 20 months we finally (and accidentally) found a solution to the problem! For the few machines, on which the service did not run properly, setting the NoInteractiveServices value in the registry to 0 did the trick. A value of 1 (which is default) means that no service is allowed to run interactively, regardless of whether it has the SERVICE_INTERACTIVE_PROCESS property. More information on Interactive Services.
I am not completely satisfied with the solution, because on all the other machines NoInteractiveServices is set to 1 AND the service runs properly anyway. However, on the machines where the service did not run interactively this solution worked for us. Thus I will accept this as an answer.
If anyone has more information on this issue and can explain why this works, feel free to
add them - I would be very interested!
There is an old OC4J server where 200+ web services are deployed. Now all have been ported to weblogic. The question is whether can I check if anyone is still accessing the webservices deployed in oc4j. Can't rely on app logs as this is quite old (not much standard followed)
If anyone is accessing is it possible to understand who is it?
PS: Am a newbie please help me in understanding this (if possible) in detail.
Much appreciated.
You can use a tool like TCPDump to locate in real-time traffic on the LAN where the destination and port number match the host/port of the running OC4J
First of all please let me be clear that I am a windows user and very new to the web world. For the past months I have been learning both python and django, and it has been a great experience for me. Now I have somehow created a small project that I would like to deploy in the production server. Since django has its built-in development server there was no problem for me. But now that I have to deploy it to a production server I googled around and found Nginx + uWSGI or Nginx + Gunicorn as the best option for it. And as uWSGI and Gunicord are incompatible with Windows, I think I should adapt Ubuntu or other Unix system.
So my questions are:
Just to be clear, as I will have to work with one of the above, please explain to me why do I need two servers?
If I have to adapt the Ubuntu environment, do I have to learn Ubuntu shell scripting, SSH and other stuff? Or the hosting provider will help me do that?
Please let me be aware of what else do I need for the above concerned.
Thank you so much for your time and please pardon if my question was a lame question. Hoping for positive response answers.
A typical configuration involves two server processes (which can be run together on the same actual hardware or virtual server) so that the proxy server in front can buffer slow clients. For instance: a slow client will connect to nginx with a request. Nginx will pass the request on to Gunicorn and Gunicorn will respond. Nginx will then consume the Gunicorn response immediately, freeing up the Gunicorn resources right away. At that point, the slow client can take as much time as it wants to consume the response from Nginx without tying up much in the way of server resources. Alternatives to the two-server-process model are to use async workers with Gunicorn and put Gunicorn itself in front, or to use an async-sync combo like Waitress. Nginx in front has the added benefit of doubling as a ready-to-use statics server, though.
Note that "slow clients" can describe: mobile phones that lose their connection and leave the TCP socket hanging until timeout mid-request; mobile phones that are just slow; unreliable connections of all types; hostile denial-of-service clients who are deliberately trying to use server resources; sometimes any old connection that has a hiccup or malfunction for any reason. So this is a problem that will affect nearly any site.
You won't need shell scripting per se but getting used to Ubuntu will take some time. There is a lot to learn even outside of scripting, like how to use the package manager, how to configure packages once they're installed in ways that won't confound future updates, etc. And you will definitely have to learn to use SSH; it is one of the most fundamental server administration tools in the *nix world.
An alternative to learning to use Ubuntu or another server platform is to use a Platform-as-a-Service option like Heroku, as PaaS hosting providers really will take care of all of that stuff for you. I recommend this approach. That having been said, even though I think PaaS is a good option for people who want to focus on development and not server admin regardless of their level of skill, it's also true that a little bit of experience with Linux server platforms goes a long way in helping you to understand the environment that your code runs in. So even if you go with PaaS, you would still benefit from tinkering with Ubuntu a little (or a lot).
Another benefit from a PaaS is that normally their infrastructure handles the Nginx part of the deal (buffering of slow requests via proxy). This is the case with Heroku, for instance. So you won't have to worry about that part of the infrastructure at all.
This part of the question is too broad to answer, but let me know in the comments if you need clarification.
I'm doing it almoast like in this tutorial: http://michal.karzynski.pl/blog/2013/06/09/django-nginx-gunicorn-virtualenv-supervisor/
Nginx is my proxy to django app running on gunicorn and its serving statics, virtualenv for my python enviroment, supervisor to watch my app's running.
It's possible you will run in some error's if not using Postgresql, ask then I will help (used MySQL in the past now it's Postgresql)
Firstly, there's no need to use Ubuntu if you're happier with Windows. I don't know if nginx works on Windows, but I'd be very surprised if it doesn't (in fact, here are the nginx docs for installing on Windows). Apache, meanwhile, definitely does work on Windows. The Django documentation has a full explanation of how to set up Apache/mod_wsgi to serve Django.
You don't need two servers. I'm not sure why you think you do: the usual reason for that is to have the static assets on a separate server, but you don't mention that as a reason. Since you're only talking about a small site, though, you don't even need to do that. One server configured to serve both Django and the static assets will do fine. Again, the docs explain exactly how to do that.
I have an Apache2 and Django (mod_wsgi) setup that provides a RESTful API. I have a set of automated tests for this, that executes ~1000 API requests (pure http GET/POST/PUT/DELETE) in sequential order.
The problem is, for every 80 requests or so, I get a strange lag/timeout for exactly 5s or 10s. See timestamp examples here:
Request 1: 2013-08-30T03:49:20.915
Response 1: 2013-08-30T03:49:30.940
Request 2: 2013-08-30T03:50:32.559
Response 2: 2013-08-30T03:50:37.597
I can't figure out why this happens. I have an apache config with KeepAlive Off (recommended setup setting for Django) but otherwise standard install for Ubuntu 12.04 LTS.
I'm running the tests from the same server where the webserver is, I first thought this was some kind of DNS cache thing, but I've added the hostname I'm requesting to /etc/hosts but the problem persists.
The system is idle and have lots of cpu and mem when this lag/timeouts happens.
The lag is not specific to a certain request (URL), it seems kinda random.
Considering that it's always exactly to the millisecond 5s or 10s, it feels like this is some specific setting somewhere causing this.
In case it provides some insight, watch my talk from PyCon US.
http://lanyrd.com/2013/pycon/scdyzk/
The talk deals with things like process churn and startup costs. One thing you shouldn't do is set maximum requests if you don't really need it.
Also consider trying New Relic to help diagnose where the issue is. That will save a lot of guessing if it is a web application of backend service infrastructure issue.
As far as seeing how such monitoring can help, watch another one of my PyCon talks.
http://lanyrd.com/2012/pycon/spcdg/
This was a DNS issue, adding the domainname I used locally to /etc/hosts actually solved the problem. I just hadn't reboot the server for the changes to take effect, thought restarting networking would take care of that, but apparently not.
Here is my scenario: I have an iPhone app (written in Monotouch but that has nothing to do with the design) that has consumables. I give 25 free consumables when the app is installed. If the user deletes the app and re-installs it, he now gets the same 25 free consumables. I need a way to prevent this.
So I came up with the idea of a database on a server (my website host?), which would have a list of UDIDs. If the user's UDID is in the database (that means he has already installed the app) a response is sent back to the app to set the consumable count to zero. If the UDID is not in the d/b, then it is added and the response is so indicated (new app).
I am thinking of using REST (simpler) and a Linux host for the server side. My questions are:
Is there a better way of doing this?
What is the language of choice on the server?
What about sqlREST? (looks very good to me, but will it work in the above scenario?)
Well, I can tell you what MY language of choice would be: ASP.NET/C# in combination with an SQL Server DB. I have my website running at a hoster which offers this combination for just a few bucks per month.
You don't even need webservices. You could just setup an ASPX page on your server and call it using NSString.FromUrl (or whatever the method is called): "mycounter.aspx?udid=1234". Everytime the page gets called, it increases the count of the passed in device ID and the only thing it ever outputs is the number of remaining requests.
Your client parses that response to integer and if it is zero, informs the user.
You should proably add some hashing to make sure that evil Krumelur won't go to your URL and call it for random device IDs, rendering them unusable. :-)
René
The answer really depends on your web host. And what they support. That probably depends on your transaction volume and so on.
Since you are using Monotouch I'm going to assume you are comfortable in .net/c# world.
I would look at a WCF web service written in c#. This in turn would use SQL server for storage. Of course you could just go straight to a SQL server stored procedure.
sqlREST looks interesting but at a glance it looks like you need to be running the Appache + Tomcat stack for that to work.
if you just want the lowest possible bar to get it working then I agree with the other poster... ASP.NET + SQL server would get it done too.